import { Pipe, PipeTransform } from '@angular/core';
import { AuthenticationService } from './authentication.service';
import { forkJoin, Observable, of } from 'rxjs';
import { map } from 'rxjs/operators';


@Pipe({
    name: 'authPipe',
    pure: true
})
export class AuthPipe implements PipeTransform {
    constructor(private authService: AuthenticationService) {
    }

    transform(linksWithRoles: { roles: string }[]): Observable<{ roles: string }[]> {
        if (!linksWithRoles) {
            return of(linksWithRoles);
        }

        return forkJoin(linksWithRoles.map(l => this.authService.isUserInRole(l.roles))).pipe(
            map(booleanFilter => linksWithRoles.filter((l, i) => booleanFilter[i]))
        );
    }
}